(Jørgensen) Lange-Bertalot 1999 Category: Symmetrical biraphid
BASIONYM: Navicula madumensis Jørgensen 1948
REPORTED AS: Navicula mandumensis (Camburn & Charles 2000, p. 24, pl. 34, fig. 4; pl. 37, fig. 1) | Kobayasia madumensis (Lange-Bertalot 1996, p. 282, fig. 18)
Contributor: Loren Bahls - May 2013
Length Range: 31.8-35.5 µm
Width Range: 5.8-6.7 µm
Striae in 10 µm: about 40
Valves are linear-lanceolate with narrow subcapitate apices. Valve length-to-width ratio ranges from 5.2 to 5.6. The axial area is very narrow. The central area is very small and elliptical in shape. The raphe is filiform with weakly expanded proximal ends. Distal raphe fissures are hooked to the same (secondary) side of the valve. Striae are strongly radiate and difficult to resolve in LM. Striae surrounding the central area do not appear to be more widely spaced than striae elsewhere on the valve. Longitudinal lines are absent.
Basionym: Navicula madumensis
Author: Jørgensen 1948
Length Range: µm
Striae in 10 µm:
Camburn, K.E. and Charles, D.F. (2000). Diatoms of Low-Alkalinity Lakes in the Northeastern United States. Academy of Natural Sciences of Philadelphia, Special Publication 18, 152 pp.
Jørgenson, E.G. (1948). Diatom communities in some Danish lakes and ponds. Det Kongelige Danske Videnskabernes Selskab, Biologiske Shrifter 5(2): 1-140.
Lange-Bertalot, H. (1996). Kobayasia bicuneus gen. et spec. nov. In: Iconographia Diatomologica, Annotated Diatom Micrographs (H. Lange-Bertalot, ed.), Vol. 4, pp. 277-287, Koeltz Scientific Books, Konigstein.
Lange-Bertalot, H. (1999). Kobayasiella nov. nom. ein neuer Gattungsname fur Kobayasia Lange-Bertalot 1996. In: Iconographia Diatomologica, Annotated Diatom Micrographs (H. Lange-Bertalot, ed.), Vol. 6, pp. 272-275, A.R.G. Gantner Verlag K.G., Vaduz.
Siver, P.A., Hamilton, P.B., Stachura-Suchoples, K. and Kociolek, J.P. (2005). Diatoms of North America. The Freshwater Flora of Cape Cod. Iconographia Diatomologica 14: 1-463.
Kobayasiella madumensis was described from a lake in Denmark. The population pictured and described on the identification page was collected from a small sub-alpine lake (elevation 1739 m) in the Mission Mountains of northwest Montana. This lake has a slightly alkaline pH (pH = 7.5) and very low concentrations of dissolved solids (specific conductance = 10 µS/cm). Camburn & Charles (2000) reported this taxon from 34 low-alkalinity lakes in the northeastern United States and Siver et al. (2005) reported it from Cape Cod.